


The Great Marriage License Mystery

by alecmagnuslwb



Category: Shadowhunters (TV)
Genre: Accidental Marriage, Alternate Universe - Human, F/F, Fluff, M/M, fluff and hangovers, other's mentioned - Freeform, tfw you may have married your future bro-in-law on a dare the night before your own wedding
Language: English
Status: Completed
Published: 2020-07-24
Updated: 2020-07-24
Packaged: 2021-03-05 04:01:55
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,971
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/25488169
Author URL: https://archiveofourown.org/users/alecmagnuslwb/pseuds/alecmagnuslwb
Summary: The morning after Clary and Izzy's bachelorette party everyone wakes up with missing time and one half of a marriage license. Who exactly married who is the question they have to try and answer before sending the brides down the aisle.
Relationships: Clary Fray/Isabelle Lightwood, Magnus Bane/Alec Lightwood
Comments: 16
Kudos: 138





	The Great Marriage License Mystery

**Author's Note:**

> I've been rewatching Smallville lately and hit the episode where Chloe and Ollie get married but they don't remember it and there came the inspiration. Enjoy!

Magnus groans, back feeling like hell. He lifts himself up and immediately falls off the couch landing directly on his already sore back onto a stack of red solo cups.

“Fuck,” he shouts out as he rolls to the side to lift himself up, a party mask on a stick digging into his side.

“Stop being so loud,” a female voice he knows well grumbles from above. Magnus finally lifts himself up into a sitting position to see Isabelle lying face down surrounded by a nest of multi colored feather boas on the couch opposite the one he’d just fallen from.

Magnus finds the inner strength to stand looking around the room. It’s his apartment, not that he remembers coming home at all, and it’s a wreck. Cups, half empty bottles of liquor and an array of party favors from the evening’s festivities cover every surface. His paintings on the walls are crooked, the strip of photobooth pictures that he and Alec had taken on their trip to Tokyo for their one-month anniversary are sitting sadly in a puddle of something. He walks over squinting his eyes against the sunlight streaming in and pics up the photo strip shaking them out best he can.

He sniffs them confirming the liquid to be vodka and not something worse. He pins them back up on the corkboard where they belong smiling at the happy looks on their faces despite the fact his head feels like there’s a tiny gnome with a hatchet running around inside of it. 

Isabelle shifts on the couch lying on her back now.

“Did we die?” she asks eyes still closed.

“Unfortunately not,” Magnus says picking up a pink cowboy hat from the chair nearest to him and plopping down into it heavily.

“What time is it?” she asks pulling a few of the feather boas around her like a blanket.

Magnus looks down at his watch about to answer when his bedroom door suddenly slams open. A flash of long red hair streaks across the apartment headed straight for the bathroom.

Clary shuts the door behind her and an unfortunate heaving sound follows. Izzy sits up quickly eager to get to her fiancée, a decision she clearly immediately regrets if the way she woozily lies back down is anything to go by.

The bathroom door swings open a moment later, Alec steps out looking disheveled as hell wearing a Hunter’s Moon t-shirt he definitely hadn’t been wearing when the night before had started.

“I don’t recommend sleeping in a bathtub when you’re 6”4,” he says voice gravelly from misuse. He squints his eyes grabbing a pair of sunglasses laying on the table as he walks past it and slips them on. “You might want to check on your fiancée, she’s throwing up half her body in there.”

Alec sits down heavily on the couch beside his sister patting her on the shoulder. She nods, takes a deep breath and centers herself standing up slowly. This time she makes it picking her way through the trash littering the floor her 8-inch heels somehow still secured to her feet.

“Your weddings in like four hours, just a reminder!” Magnus shouts and wishes he hadn’t. Judging from the way Alec plugs his ears and Izzy flips him off no one else does either. Hangovers all around it seems, a sign of a good bachelorette party.

Magnus listens for a few moments to Isabelle softly reassuring Clary, heels clicking on the tile of the bathroom floor. He looks over at his boyfriend once again heaving himself to stand and flop down beside him on the bed of boas.

“Good morning baby,” Alec grumbles lifting his arm and wrapping it around Magnus’ shoulders. Magnus hums reaching up and entangling his fingers with Alec’s. He shifts enough to toss his legs over Alec’s and looks down noticing a piece of white paper sticking out from his pocket.

He raises his eyebrows leaning back enough to pull the paper from his pocket. He unfolds it and practically jolts up from the couch. In looping script that looks like Isabelle’s is his name and what appears to be one half of a marriage license.

“Ummm Magnus!” Isabelle yells rushing out of the bathroom and directly to them on the couch. Alec shifts seemingly having fallen back asleep. She shakes a piece of paper in his face almost identical to his half. “This was in MY pocket.”

Magnus takes it from her lining it up with his. A piece of the full sheet is still missing only the last name Lightwood on Isabelle’s section the first name missing. She falls beside him seeing the almost full document.

“There’s no way,” he says laughing nervously. There’s no way.

Isabelle is just as alert as he in now, eyes in a panic. Alec sits up taking off his sunglasses. He looks from the papers to Magnus’s eyes, his eyes just as wide as his sisters.

“I also have this,” she says holding up her left hand revealing a diamond band on her thumb. “It’s stuck.”

“That’s one of mine,” Magnus says looking down at one of his empty fingers. “Oh, shit that’s one of mine.”

Alec falls back into the couch, no longer pressed into Magnus’ side.

“Oh my god, oh my god, oh my god,” Isabelle says dropping her head into her hands.

Clary comes out of the bathroom, eye makeup resembling a raccoon with a huge bottle of mouth wash in her hands. Chairman Meow appears circling around her socked feet trying to trip her up, she takes it in stride and steps over him easily. 

“Just in case,” she says when she notices Alec judging the bottle. “So, I’m guessing from those repetitive oh my gods it’s not us that got married last night.”

“No,” Isabelle moans dramatically throwing herself on the ground, arms tossed over her eyes. “I married my brother’s boyfriend probably as a dumb joke or something the night before my wedding. Jace will never let me live this down.”

“We don’t know that. It just says Lightwood, it could be us!” Magnus argues looking at his boyfriend uncertainly. Alec looks a little bit like a deer in the headlights so Magnus scrambles. He’s not really sure what’s the better option: accidentally marrying your boyfriend of two months in a drunken stupor or marrying your boyfriend’s sister as a joke in a drunken stupor. At least he hopes it was a dumb joke if it’s the latter, the former well he’s not sure if he and Alec are ready to get into that no matter how quickly their relationship has progressed. “Or you know it’s fake, fake is an option.”

Clary steps over inspecting the paper.

“Paper’s too high quality for a fake,” she shrugs sitting down on the coffee table. Magnus gives her a pointed look, making it clear she’s not helping this situation.

The four of them sit there silently for a while. Alec is the first to speak up.

“Okay, what does everyone remember from last night? Let’s piece this together,” he says reasonably opening the floor to whoever wants to start.

It takes about twenty minutes but they get a vague timeline from memory and other evidence pulled from their pockets. They scour the apartment as they talk making hangover remedies while desperately searching for the missing piece of the license.

So far they’ve determined things started here, pre-gaming with cocktails and dinner then it was the Hunter’s Moon where Magnus absolutely demolished Alec in a series of pool games. That’s when Alec lost his shirt as well, a beer spilled on him by Jace who’d already had far too much to drink. Magnus had forgotten the detail, but Alec recalls it with annoyed clarity.

After the Hunter’s Moon, Jace had been sent home in a cab, Maia, Bat and the rest of their friends had come along with them to Pandemonium and that was where things got blurry. By 11:30 their friends had all called it a night, but the four of them had hit the dancefloor. Dancing then turned into competition when Izzy had challenged Magnus and Alec to a couple’s tequila shot off. Magnus assumes they won considering how Clary handles her liquor.

Then it all goes well and truly blank for each of them. Clary’s phone is missing entirely, Alec’s is dead and seemingly has been since at least midnight. Izzy’s phone is just a series of back and forth drunken texts with Jace that are increasingly sarcastic and misspelled.

Magnus is the only one with a possible lead. There’s evidence of a Lyft being called that took them to the venue where Izzy and Clary are getting married in mere hours and a 15-minute call with Raphael somewhere around one in the morning.

Magnus dials his number immediately hoping for answers.

“You asked me to go through the whole ceremony,” Raphael says after five minutes of making fun of them all. Magnus’ childhood best friend never did finish the process of becoming a full-blown preacher, not finding it for him in the end, but he’s ordained for weddings and had happily offered to do the ceremony when Clary and Izzy still hadn’t found someone two weeks before.

“Why?” the four ask in frustrated unison.

“Dios, I don’t know. You were all trashed but you insisted, so to get you to leave me alone because some of us who are involved in this wedding wanted to get a good night’s rest, I went through the whole thing, start to finish,” he explains.

“Did vows get exchanged or anything?” Alec asks.

“Not really, but you did all say ‘I do’ at some point I couldn’t tell who though, I’m pretty sure you were all outside,” Raphael answers. “Which in theory I guess would mean someone got married, but not that it matters I mean ordained or not without a license it’s not legally binding.”

They all sigh.

“That’s the problem,” Magnus grumbles. They end the call after that saying goodbyes and see you soons.

“Alright,” Alec says sounding the level headed big brother and leader he always is. “Here’s the plan’ everyone needs to shower first. We’re short on time so that means couples, no funny business though. Raphael said we were outside, so that probably means we couldn’t get into the venue when we decided to go. Magnus and I can ask around while the two of you get ready since we have to be there anyways.”

Everyone nods their heads in agreement.

“And what do we do if it was us that got married?” Magnus asks gesturing between him and Izzy.

They’re all silent. Clary is the first to pipe up, taking this whole situation surprisingly well. Maybe throwing up half of one’s body weight brings clarity.

“I mean only the four of us saw it, it hasn’t been officially filed, just signed and if we give Raphael permission to mock us about it for the rest of our lives he won’t say anything to anyone else,” she reasons.

She grabs Izzy’s hand pulling her to the shower leaving no room for argument.

Magnus blows out a long breath leaning against the kitchen counter where they’d all gathered. Alec joins him, crossing his arms.

“Are you mad I may have accidentally married your sister?” Magnus says quietly.

Alec snorts.

“No, we were all beyond drunk last night and knowing you and Izzy it was some competitive dare that went a step too far.”

Magnus chuckles, that does sound like them.

“And what if,” he pauses a little worried. “What if it was us that accidentally got married?”

Alec turns reaching up to pull a piece of confetti from Magnus’ hair. His hand slides down brushing Magnus’ cheek.

“Then we got married,” he shrugs.

Isabelle’s phone rings breaking the moment, on today of all days he’s fairly certain she’d appreciate them picking it up. It’s the caterer and the call takes long enough that he and Alec have barely five minutes for a shared shower before calling a cab to get to the venue. They don’t get to talk about Alec’s casual shrug about them being married like it wouldn’t be a big deal.

Once they’re at the venue people start filing in Maryse and Maia take charge of Isabelle while Clary is drifted away by Simon and Jace. They both lock eyes with Magnus and Alec trusting them to get answers or burn the pieces of marriage license before the days over.

Alec is the first to be fully ready so he heads around to ask the staff some questions. He eventually is led to the night security guard who simply shrugs saying he’d fallen asleep on the job. The only evidence that they were even there is in the form of Magnus’ Lyft history and a feather boa exactly like the ones in Magnus’ apartment tangled in a bush outside. Alec sends him a picture of it attached with the message, ‘I have a feeling we’re going to be finding these around New York for the rest of the year.’

Everything goes by in a rush after that. Magnus never gets the chance to bring up anything to Alec as they take their places as groomsmen.

The wedding is beautiful, Raphael does an excellent job so much so that Clary’s stepdad bursts into tears only two lines in. Clary and Izzy exchange vows that make everyone else cry and Izzy dips Clary as they kiss to everyone’s delight. They look the happiest they’ve ever been, clearly no longer thinking about the possible mistake marriage that was.

Magnus however can’t think of anything else. The sun has fallen and the cake has been cut by the time he gets a moment alone with Alec. He steps outside for some fresh air just beside the bushes where the feather boa still flaps in the wind and Alec slips out behind him. Two long arms wrap around his waist and Magnus leans back into a strong chest.

They stand there quietly, the muffled sound of music behind them.

“You know,” Magnus says eventually. “You were pretty casual about the concept of us being accidentally married this morning.”

Alec once again the picture of nonchalance just shrugs.

“I mean at first it was a lot, but once the worst of the hangover subsided I realized if it was us well, that’s not the worst thing. I love you; I have intentions to be with you for as long as you’ll have me so that works.”

Magnus shifts so that Alec is standing in front of him eyes a little glassy. Alec takes the tears to be a bad thing.

“I get it though if it’s way too soon to be thinking or saying anything like that, or,” Alec freezes as Magnus puts a finger in front of his lips.

“I feel the same way,” he smiles. “I mean it’s not ideal and like Clary said it’s not official till it’s filed, but I do feel the same way. I have no doubt in my mind we’re heading that way one day.”

Alec smiles kissing the tip of Magnus’ finger where it still rests against his lips. He pulls Magnus into a hug. Magnus rests his chin on Alec’s shoulder eyes still open and that’s when he spots it. The feather boa shifts in the wind and a small white piece of paper is revealed skewered on the prickly end of the bush.

He pulls back from Alec leaping down the two small steps to pick the piece of paper from the bush.

“Well I’ll be damned,” he says snatching up the sliver of paper and flipping it over. The missing piece of the license. Alec steps over, joining him.

“Is that what I think it is?” he says looking over Magnus’ shoulder.

Magnus nods holding it up for Alec to read. Alec smiles, pulling the Lightwood piece he’d been holding onto from his pocket as Magnus does the same with his part.

 _Alexander_ the missing piece reads in Isabelle’s looping script.

“Guess your stuck with me now,” Magnus says with a smirk.

Alec rolls his eyes fondly.

“Technically it hasn’t been filed, so not officially,” he jokes, pulling Magnus in by the waist. “Plus it’s in three pieces I don’t think the courthouse is going to accept it.”

“Pfft, it just needs a little tape,” Magnus says gathering the three pieces of paper and folding them carefully before placing them in the inner pocket of his wine-red jacket a compliment to Alec’s black one and Isabelle’s deep red dress. “Plus, Clary’s stepdad is the Mayor, we can totally get some strings pulled.”

Alec laughs shifting to drape his arms over Magnus’ shoulders.

“You mean it?” he asks.

Magnus nods. “We have to have a party bigger than this one at some point though,” he says gesturing back to the reception hall. “I have a reputation to uphold.”

“Of course,” Alec says seriously. “So we’re gonna be Mr. and Mr. Lightwood then?”

Magnus hums tapping a finger to his chin in thought.

“I was thinking Mr. and Mr. Bane actually.”

“I like the sound of that,” Alec says before pulling Magnus into a kiss.

They never do piece together the night exactly. Eventually Izzy gets the ring off her thumb and it fits Alec’s ring finger perfectly they discover, Magnus in turn realizes he has an exact double of it that he starts wearing himself. Why Isabelle filled out the license or if they kissed after they said I do or even actually said it is never truly answered.

Their actual marriage will be a mystery for the rest of their lives, but Magnus does get his party an acceptable six months after Clary and Izzy’s.

**Author's Note:**

> As usual, find me on tumblr: [alecmagnuslwb](https://alecmagnuslwb.tumblr.com/)


End file.
